This is a continuation-in-part application to a patent application Ser. No. 07/477,488 entitled "Inertia Force Flowmeter" filed on Feb. 9, 1990. One of the most popular methods for measuring mass flow rate through a conduit is to induce a flexural vibration of the conduit and measure the deviation in the mode of flexural vibration of the conduit containing moving media from that of the conduit containing stationary media as a measure of mass flow rate, which principles have been employed in the construction and operation of a family of flowmeters commonly known by the name of Coriolis Force or Convective Inertia Force flowmeters. As the magnitude of deviation in the mode of flexural vibrations of the conduit resulting from the moving mass in the conduit is usually very small, the Coriolis Force or Convective Inertia Force flowmeter is not capable of measuring the mass flow rates of liquid media moving at low velocities as well as that of gaseous media moving at moderately high velocities. Since the vibrating conduit or conduits employed in the Coriolis Force or Convective Inertia Force flowmeters are constantly and continuously vibrated, the vibrating conduit or conduits are vunerable to failure due to fatigue of the conduit material. The Coriolis Force or Convective Inertia Force flowmeter cannot have a large diameter flow passage, as it is totally impractical to induce and maintain a flexural vibration of conduits of diameter greater than two inches. The present invention teaches construction and operation of a mass flowmeter comprising one or more conduits which are not vibrated, and have diameters as small as a fraction of an inch or as large as several inches.